Safety-valve



J. G ."WHITB.- SAFETY VALVE.

(No Model.)-

No. 549,986. "P99 11969 Nov. 19, 1895.

I A z James Emfla.

UNITED STATES PATENT OFFICE.-

JAMES G. WHITE, OF WESTPORT, MISSOURI.

SAFETY- VALVE.

SPECIFICATION forming part of Letters Patent No. 549,986, dated November 19, 1895. Application filed January 31, 1895. Serial No. 536,781. (No model.)

To all whom it may concern:

Be it known that 1, JAMES G. WHITE, a citizen of the United States, residing at WVestport, in the countyof Jackson and State of Missouri, have invented'certain new and useful Improvements in Safety-Valves, of which the following is a specification, reference being had therein to the accompanying drawings.

My invention relates to improvements in safety-valves, and pertains to-the class of safety-valves provided with an expiratory and an inspirating valve.

The object of myinvention is to provide a safety-valve comprising an upper and a lower shell, an expiratory and an inspirating valve independently seatedin'one of the shells, by means of which the valves may operate one independently from the other.

My invention consists, further, in peculiarities of construction hereinafter fully described and claimed, by means of which the valves may be readily adjusted for the pressure required in the vessel on which they are used.

In the accompanying drawings, illustrating the invention, Figure 1 represents a vertical sectional .view. Fig. 2 represents an elevation view. Fig. 3 represents a top view of the lower shell and lower valve, the upper valve being removed. Fig. 4 represents a plan view of the guide-plate for the lower valve. Fig.

5 represents a bottom view of the upper valve. Fig. 6 represents the upper tension-plug in vertical section and an elevation view of the upper valve-stem.

Similar letters of reference indicate similar parts.

Referring to the drawings, A indicates the lower half of the valve-casing, which is substantially tubular in shape, the lower end being externally screw-threaded, so that the valve may be secured to the boiler, steamchest, cylinder, or other vessel with which it is used. The portion of the lowershell immediately above the screw-threaded lower end is provided with a polygonal flange B, by

which the valve may be seized with a wrench when screwing it into or out of the place where it is secured.

The upper end' of the shell A is provided with a horizontallyprojecting externallyscrew-threaded flange O, which .is fitted to the internally-screw-threaded' lower end of the upper shell D. The shell D is cylindrical in form, the lower end being open and the upper end being closed and provided with a central boss E,- through which is a vertical screw-threaded opening. The upper end of the shell A is provided with a valve-seat, to which is fitted the expiratory valve F, said valve being substantially a cylindrical body providedwitlivertical wings G, located around its periphery and movably fitted within the central opening in the lower shell A. A beveled flange at the top of the flange F is fitted to the valve-seat in the upper end of the said shell. A central vertical opening extends from the top of the valve F partially through the valve. Within this opening is fitted a vertical valve-stem H, the upper end of which passes through and is guidedv in a central vertical opening in a tension-plug I, which is cylindrical in shape, externally screw-threaded, and fitted to the opening in the boss E.

The upper end of the tension-plugI is preferably square in shape, as indicated by J, so

that a wrench may be applied to it for adjusting purposes. An internally screwthreaded cap K, provided with a polygonalshaped flange L, is fitted to the upper end of the tension-plug I and serves as a lock-nut when screwed against the upper face of the boss E. A coiled spring M encircles the stem H, the lower end of the spring having abearing upon the upper side of a horizontal flange on the valve-stem H, located above the valve F. The upper end of the spring M has a bearing upon the lower sideof a horizontal flange 0, located at the lower end of the tension-plug I.

The flange C is vertically fluted around its periphery, as indicated by P, thus providing openings through which steam may escape from the interior of the shell D.

The lower valve Q has the shape of a hollow cylinder, the upper end being open and the lower end closed, with the exception of vertical openings therein, as indicated by R. The lower endof the cylindrical portion of the valve Q is provided with a beveled flange, which is fitted to a correspondingly beveled inwardly-projecting portion on the inner surface of the shell A, thus providing a seat for the lower valve. The upper part of the cylinder Q has its periphery fitted to the open ing through the shell A. An external peripheral groove S is provided in the enlarged portion of the valve Q. Openings T, extending through the shell A, are located opposite the groove S and communicating therewith. The valve Q is provided at its lower end with a central vertical stem U, the lower end of which is guided in avertical opening V, centrally located in the bottom of a horizontal guide-plate \V, the upper side of which is provided with a vertical externally -screwthreaded flange X, which is fitted to the internally-screw-threaded lower end of the shell A. The guide-plate \V is provided with vertical openings Y, extending therethrough. The valve Q is normally held in place near its valve-seat by means of a coiled spring Z, encircling the valve-stem U and having a bearing at its lower end upon the plate W' and at its upper end against the lower side of the enlarged portion of the valve Q. The function of the spring Z is to assist the steampressure in closing the valve Q; but the spring should not hold the valve seated when there is no steam-pressure.

My invention is operated as follows: The base portion A is screwed into the screwthreaded opening in the boiler or other vessel with which the valve is to be used. The cap L is removed and the tension-plug adjusted to the proper position by screwing it upward or downward, thereby compressing or removing pressure from the coiled spring M, which serves to hold the valve F close to its seat. The valve l\[ should be sufiiciently strong to withstand the pressure required only to be kept within the boiler. The lower valve Q is held in its seat by the spring Z, which may be comparatively a light one, as it is required to support the valve Q near its seat, so that the stea1n-pressure may easily close it. \Vhen the pressure of the steam within the vessel is sufficiently strong, the valve F is raised, permitting the steam to escape from the vessel through the openings Y and R and into the upper casing, from which it escapes through the flutings P into the air. I11 case a vacuum is formed in the boiler, steamchest, or other vessel to which the valve is attached, the pressure holding the valve Q in its seat is removed and the valve drops by gravity from its seat, permitting the air to reach the boiler through the openings T, groove S, and openings Y.

In some instances, as in use upon a 1000- motive steam-chest, the spring Z may be dispensed with.

In Letters Patent granted to me and bearing (late December 13, 1892, and in an application for a patent filed by me May 29, 1894, are shown and described a safety-valve in which. an inspirating and an expiratory valve are combined in one casing, one of the valves being seated upon a rigid portion of the valve and the other valve beingprovided with a seat in the first valve. In the constructionstherein shown it was necessary to use a spring against the lower valve as strong, it not stronger, in tension as the spring operating upon the upper valve; but in the construction shown herein the operation of the two valves is entirely independent one from the other, thus permitting a very light spring to be used to operate the vacuum-valve. In the present invention the necessity of providing means for regulating the tension of the lower-valve spring is obviated.

Having thus described my invention, what I claim, and desire to secure by Letters Iatcut, is-

1. In safety valves the combination with an inclosin g casing, of an escape valve and a vacuum valve each provided with a rigid seat within the casing, and independent inlet and outlet openings for the two valves, substan tially as described.

2. In safety valves, the combination with an. inclosing casing, of an escape valve and a vacuum valve each having a rigid. seat within the casing, outlet openings leading through the vacuum valve to the escape valve, and. independent inlet openings leading to the vacuum valve, substantially as described.

In safety valves, the combination with an inclosing casing, of an escape valve and a vacuum valve each having a rigid seat within the casing, outlet openings leading through. the vacuum valve to the escape valve, an. adjustable load upon the escape valve, and independent inlet openings leading to the vacuum, substantially as described.

4. In safety valves, the combination with an. inclosing casin g, of an escape valve and a vacuum valve each having a rigid seat within the casing, outlet openings leading through the vacuum valve to the escape valve, an adjustable load upon the escape valve, means for locking when adjusted, and independent inlet openings leading to the vacuum valve, substantially as described.

5. In safety valves, the combination with an upper anda lower shell, of an escape valve and a vacuum valve independently seated within the lower shell, outlet openings leading through the vacuum valve to the escape valve and upper shell, outlet openings therefrom, and inlet openings in the lower shell leading to the vacuum valve, substantially as described.

(i. In safety valves, the combination with. an upper shell, of a lower shell having screwthread connection therewith, an escape valve and a vacuum valve independently seated within the lower shell, a spring tension holding the escape valve in its seat, means for regulating the amount of said tension, and suitable inlet and outlet openings, substantially as described.

7. In safety valves, the combination with an upper and lower shell, an upper and a lower seat in the lower shell, valves seated thereon, In testimony whereof I affix my signature suitable inlet and outlet openings to said in presence of two witnesses. valve, a spring holding the upper valve in place, a tension plug having a screw-thread JAMES G. WHITE. 5 connection with the upper shell and bearing Witnesses:

against said spring, substantially as de- WARREN D. HOUSE,

J F. HADLEY.

scribed. 

